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Table 1 Distance drifted and time from release to last recorded movement in the entire tracking period for groups of dead Atlantic salmon smolts and European silver eels tagged with radio transmitters and released in three German rivers, related to water discharge at release

From: Movements of dead fish in rivers

Species River Release site Release date Number of fish Total distance (km) drifted during entire study period Mean (min–max, SD, median)a Time (days) from release to last recorded downstream movement Mean (min–max, SD, median)b Water discharge (m3 s−1) at release Distance (km) drifted during first period after release Mean (min–max, SD, median) Period length (days) Water discharge (m3 s−1) in period after release Mean (min–max, SD, median)
Salmon Sieg Tailrace 9 Apr 15 10 1.3 (0.1–2.4, 0.7, 1.5) 3.2 (1.6–4.5, 1.6, 4.5) 20.2 1.3 (0.1–2.4, 0.7, 1.5) 24 9.5 (5.5–20.2, 3.6, 8.8)
Salmon Sieg Tailrace 16 Apr 15 10 0.9 (0.1–1.9, 0.6, 0.9) 9.0 (1.7–22.7, 7.9, 6.7) 9.9 0.9 (0.1–1.9, 0.6, 0.8) 21 8.0 (5.5–15.7, 2.1, 7.6)
Salmon Kinzig On turbine 13 Apr 15 10 0.05 (0–0.2, 0.1, 0) 13.5 (1.7–25.7, 12.6, 12.7) 21.0 0.03 (0–0.1, 0.05, 0) 24 27.5 (11.0–120.0, 22.8, 17.0)
Salmon Kinzig On turbine 18 Apr 15 10 0.03 (0–0.1, 0.05, 0) 7.4 (0.5–22.8, 10.0, 0.5) 17.0 0.0 (0–0, 0, 0) 23 29.7 (11.0–120.0, 24.0, 17)
Salmon Diemel Archimedes 10 Apr 15 10 0.5 (0.4–1.1, 0.3, 0.4) 1.5 (0.04–11.2, 3.4, 0.5) 15.5 0.6 (0.4–1.1, 0.4, 0.4) 22 10.8 (8.3–15.5, 2.0, 10.6)
Salmon Diemel Archimedes 15 Apr 15 10 0.3 (0.1–0.7, 0.2, 0.2) 2.6 (0.2–9.5, 3.4, 0.5) 12.5 0.3 (0.1–0.7, 0.2, 0.15) 23 9.6 (7.6–13.6, 1.3, 9.3)
Eel Sieg Tailrace 8 Oct 14 5 13.3 (2.7–21.1, 7.7, 14.6) 27.9 (0.8–54.8, 31.0, 28.1) 14.1 11.7 (2.7–15.1, 6.0, 14.4) 55 20.0 (7.1–81.2, 13.1, 14.3)
Eel Sieg Tailrace 10 Oct 15 10 7.5 (1.1–19.7, 6.4, 5.8) 41.9 (9.6–107.6, 26.4, 41.6) 5.5 7.1 (1.1–19.7, 6.5, 4.1) 60 31.7 (3.4–227.0, 47.0, 5.8)
Eel Sieg Tailrace 13 Oct 15 10 8.2 (0.1–15.4, 5.8, 9.45) 34.5 (1.7–43.7, 17.4, 43.7) 4.1 7.7 (0.1–15.4, 6.0, 8.4) 59 32.8 (3.4–227.0, 47.0, 6.2)
Eel Sieg Tailrace 21 Nov 15 5 5.8 (0.0–18.5, 7.3, 2.8) 28.8 (0.03–66.0, 29.3, 20.0) 74.7 5.4 (0–16.5, 6.5, 2.8) 59 52.6 (17.4–227.0, 41.4, 39.0)
Eel Sieg Spillway gate 21 Nov 15 5 6.2 (1.9–12.9, 4.8, 3.7) 14.8 (0.03–59.1, 24.8, 5.0) 74.8 5.0 (1.9–9.5, 4.0, 3.7) 59 52.6 (17.4–227.0, 41.4, 39.0)
Eel Kinzig On turbine 12 Oct 15 5 13.0 (0.7–30.1, 12.4, 10.5)c 44.2 (39.2–58.9, 9.8, 39.4)c 3.7 12.8 (0.1–30.1, 12.6, 10.5)c 59 11.2 (2.7–141.0, 18.0, 3.5)
Eel Kinzig On turbine 21 Nov 15 5 17.7 (7.0–30.1, 11.6, 13.6)c 10.9 (8.4–18.8, 4.4, 9.0)c 32.0 17.7 (7.0–30.1, 11.6, 13.6)c 19 24.8 (9.4–141.0, 23.3, 16.0)
Eel Diemel Tailrace 9 Oct 14 5 1.2 (0.4–2.9, 1.1, 0.5) 24.4 (2.6–54.6, 27.6, 6.6) 11.4 1.3 (0.5–2.3, 0.9, 1.2) 55 8.1 (5.8–14.7, 1.5, 7.8)
Eel Diemel Archimedes 9 Oct 14 5 1.8 (0.2–5.1, 2.0, 1.2) 39.5 (5.8–54.6, 22.1, 54.6) 11.4 0.7 (0.1–1.3, 0.6, 0.7) 55 8.1 (5.8–14.7, 1.5, 7.8)
  1. Distance drifted in the first period after release is also included, i.e., during approximately the first 3 weeks for Atlantic salmon and first 2 months for European silver eels (exact length of period is given and varies among groups due to differences in tracking dates), in relation to water discharge during that period. Fish taken by scavengers are not included in drift in the first period after release. Data on water discharge were obtained from Schwaibach gauging station in River Kinzig (1.9 km upstream of Gengenbach power station), from Haeuda weir in River Diemel (5.4 km downstream of Kuhlemühle power station) and from Unkelmühle power station in River Sieg
  2. aFor scavenged fish or fish with an uncertain fate, this is based in maximum distance drifted before they disappeared or moved upstream
  3. bTime from release to the tracking survey preceding the tracking survey when the fish were recorded on their most downstream position
  4. cMean, median and max are minimum numbers, because the eels were not followed downstream of the confluence with the Rhine (30.1 km downstream)